The Medicine Cabinet-Ask the Harvard Experts: How to handle a tick bite

A: Tick bites are usually harmless. They may cause a raised, reddened area or a minor allergic reaction at the site of the bite. However, if the tick is infected with bacteria, viruses or protozoa, these infections can be transmitted. And they can be serious. Examples include: Lyme disease, Babesiosis, Anaplasmosis, Human monocytic ehrlichiosis, Tularemia, Rocky Mountain spotted fever, and Colorado tick fever.

My recommendations about how to handle a tick bite depend on a number of factors, including:

1. Where you live

2. The appearance of the tick and whether it was attached or filled with blood when you found it

3. How recently the bite occurred

4. The presence of symptoms or signs that could be related to a tick-related disease (see below)

If the tick is still attached when you discover it, remove it right away. Apply tweezers close to the skin, and gently pull the head straight out of the skin without twisting. Try not to squeeze the body. Wash the bite with soap and water. Save the tick in a sealed container or plastic bag in case your doctor wants to see it or send it for analysis.

If you've been bitten by a tick, call your doctor for evaluation and possible treatment if you:

3. Live in an area where Lyme disease is common, especially if the tick was filled with blood, attached for more than 24 hours, and the bite occurred within the last three days. Taking an antibiotic after a high-risk tick bite can prevent Lyme disease from developing.